McCallum served seven points in a row at one point in the match, including four aces. That gave the Panthers the momentum they needed to win the match.
Hesperia won 25-20, 17-25, 25-15, 25-17.
Emma Joppich chipped in with three aces and six kills. McCallum, Elli McAgree and Natalee Taylor also had six kills. McCallum also had 14 digs and 14 assists.
Newcomer Ali Townsend also had 14 digs to help the Panthers on defense.
The busy slate continues for Hesperia with a tournament in Cadillac on Friday and Fremont on Saturday. Conference action returns to Hesperia on Wednesday against Lakeview.